diff --git a/src/composables/ai/useAiWindow.ts b/src/composables/ai/useAiWindow.ts
index feacbe1..0f915c8 100644
--- a/src/composables/ai/useAiWindow.ts
+++ b/src/composables/ai/useAiWindow.ts
@@ -4,13 +4,12 @@
 //! - _unlistenMove / _unlistenResize: 主窗口 move/resize 跟随的 unlistener
 //!
 //! 耦合:
-//! - detachPanel/resumeInDetached 调 useAiConversations.switchConversation
-//! - resumeInDetached 调 aiShared.nextMsgId 占位 ai 气泡
+//! - resumeInDetached 调 aiShared.nextMsgId 占位 ai 气泡 + invoke('ai_is_generating') 核对后端真值
 //! - reattachPanel/detachPanel 调 useAiPanel.persistUiState
 
+import { invoke } from '@tauri-apps/api/core'
 import { state } from '../../stores/ai'
 import { nextMsgId } from './aiShared'
-import { switchConversation } from './useAiConversations'
 import { persistUiState } from './useAiPanel'
 
 // ── 主窗口事件跟随 unlistener ──
@@ -54,6 +53,8 @@ async function detachPanel() {
   win.once('tauri://destroyed', () => {
     state.detached = false
     state.docked = false
+    // R3: X 关分离窗口后主面板自动恢复,无需手动 Ctrl+I
+    state.panelOpen = true
     stopFollowMain()
   })
   state.detached = true
@@ -77,10 +78,26 @@ async function reattachPanel() {
 
 /** 分离窗口挂载时接管主窗口当前对话(含生成中态) */
 async function resumeInDetached(convId: string | null) {
-  const id = convId || state.activeConversationId
-  if (id) await switchConversation(id)
+  // R5: 不自动 switchConversation —— 分离窗口可看历史列表,但不主动覆盖主窗口 activeConversationId
+  //     (避免主窗口期间发消息落错会话)。若需切换会话,由用户在分离窗口显式操作触发。
+  void convId
   const gen = localStorage.getItem('df-ai-gen')
   if (gen) {
+    // R4: 先核对后端 ai_is_generating 真值,generating=true 才重建生成态,
+    //     避免 df-ai-gen 残留导致假气泡 + 130s 后 watchdog 假超时
+    let backendGenerating = false
+    try {
+      backendGenerating = await invoke<boolean>('ai_is_generating')
+    } catch (e) {
+      console.error('[AI] resumeInDetached: 核对 ai_is_generating 失败,跳过重建生成态', e)
+      return
+    }
+    if (!backendGenerating) {
+      // 后端已不再生成,清残留快照,不重建
+      localStorage.removeItem('df-ai-gen')
+      localStorage.removeItem('df-ai-text')
+      return
+    }
     // 接管正在生成的对话:恢复已生成文本并补占位,后续 delta 继续追加
     state.currentText = localStorage.getItem('df-ai-text') || ''
     state.messages.push({